1. Field of the Invention
The present invention relates to a color cathode ray tube having a fluorescent surface with an optical filter and a fabrication method thereof.
2. Description of the Related Art
Many color cathode ray tubes that are conventionally used each have an optical filter layer disposed between a glass panel and a fluorescent substance layer so as to improve the brightness and contrast of the fluorescent surface. The fluorescent surface is composed of an optical filter layer and a fluorescent substance layer. The optical filter layer is formed on an inner surface of the glass panel that has a black matrix pattern or a black stripe pattern that has portions that transmit rays of light with wavelengths red, green, and blue. The fluorescent substance layer has portions that emit rays of light of red, green, and blue.
On the fluorescent surface, a fluorescent substance is directly formed on the optical filter layer composed of very fine particles. Thus, the fluorescent substance layer closely contacts the optical filter layer. Consequently, the fluorescent substance layer tends to be affected by the optical filter layer. Thus, fluorescent substance particles tend to reside at different color dots. In addition, on the fluorescence surface, the optical filter layer does not sufficiently adhere to the fluorescent substance layer. Consequently, fluorescent substance particles may break and drop.